# Define here the models for your spider middleware
#
# See documentation in:
# https://docs.scrapy.org/en/latest/topics/spider-middleware.html

# from scrapy import signals
#
# # useful for handling different item types with a single interface
# from itemadapter import is_item, ItemAdapter
#
#
# class ScrapypyppeteerdemoSpiderMiddleware:
#     # Not all methods need to be defined. If a method is not defined,
#     # scrapy acts as if the spider middleware does not modify the
#     # passed objects.
#
#     @classmethod
#     def from_crawler(cls, crawler):
#         # This method is used by Scrapy to create your spiders.
#         s = cls()
#         crawler.signals.connect(s.spider_opened, signal=signals.spider_opened)
#         return s
#
#     def process_spider_input(self, response, spider):
#         # Called for each response that goes through the spider
#         # middleware and into the spider.
#
#         # Should return None or raise an exception.
#         return None
#
#     def process_spider_output(self, response, result, spider):
#         # Called with the results returned from the Spider, after
#         # it has processed the response.
#
#         # Must return an iterable of Request, or item objects.
#         for i in result:
#             yield i
#
#     def process_spider_exception(self, response, exception, spider):
#         # Called when a spider or process_spider_input() method
#         # (from other spider middleware) raises an exception.
#
#         # Should return either None or an iterable of Request or item objects.
#         pass
#
#     def process_start_requests(self, start_requests, spider):
#         # Called with the start requests of the spider, and works
#         # similarly to the process_spider_output() method, except
#         # that it doesn’t have a response associated.
#
#         # Must return only requests (not items).
#         for r in start_requests:
#             yield r
#
#     def spider_opened(self, spider):
#         spider.logger.info("Spider opened: %s" % spider.name)
#
#
# class ScrapypyppeteerdemoDownloaderMiddleware:
#     # Not all methods need to be defined. If a method is not defined,
#     # scrapy acts as if the downloader middleware does not modify the
#     # passed objects.
#
#     @classmethod
#     def from_crawler(cls, crawler):
#         # This method is used by Scrapy to create your spiders.
#         s = cls()
#         crawler.signals.connect(s.spider_opened, signal=signals.spider_opened)
#         return s
#
#     def process_request(self, request, spider):
#         # Called for each request that goes through the downloader
#         # middleware.
#
#         # Must either:
#         # - return None: continue processing this request
#         # - or return a Response object
#         # - or return a Request object
#         # - or raise IgnoreRequest: process_exception() methods of
#         #   installed downloader middleware will be called
#         return None
#
#     def process_response(self, request, response, spider):
#         # Called with the response returned from the downloader.
#
#         # Must either;
#         # - return a Response object
#         # - return a Request object
#         # - or raise IgnoreRequest
#         return response
#
#     def process_exception(self, request, exception, spider):
#         # Called when a download handler or a process_request()
#         # (from other downloader middleware) raises an exception.
#
#         # Must either:
#         # - return None: continue processing this exception
#         # - return a Response object: stops process_exception() chain
#         # - return a Request object: stops process_exception() chain
#         pass
#
#     def spider_opened(self, spider):
#         spider.logger.info("Spider opened: %s" % spider.name)



from pyppeteer import launch
from scrapy.http import HtmlResponse
import asyncio
import logging
from twisted.internet.defer import Deferred

logging.getLogger('websockets').setLevel('INFO')
logging.getLogger('pyppeteer').setLevel('INFO')

def as_deferred(f):
    return Deferred.fromFuture(asyncio.ensure_future(f))

class PyppeteerMiddleware(object):
    async def _process_request(self, request, spider):
        browser = await launch(executablePath='D:\chrome-win\chrome.exe',
                               headless=False)
        page = await browser.newPage()
        pyppeteer_response = await page.goto(request.url)
        await asyncio.sleep(5)
        html = await page.content()
        pyppeteer_response.headers.pop('content-encoding', None)
        pyppeteer_response.headers.pop('content-Encoding', None)
        response = HtmlResponse(
            page.url,
            status=pyppeteer_response.status,
            headers=pyppeteer_response.headers,
            body=str.encode(html),
            encoding='utf-8',
            request=request
        )
        await page.close()
        await browser.close()
        return response

    def process_request(self, request, spider):
        return as_deferred(self._process_request(request, spider))
